Bird Question?

So, a couple days ago, I spotted some "big birds" hanging out in a tall tree next to Ronald Bog.

Ronald Bog hosts many types of birds, including heron, many kinds of ducks and geese, swallows and even an osprey this summer.

But, I'd love your input on this one as a break from election day frenzy.
Please let me know what these are? Are they Loons, Grebes, or Cormorants?
Seattle Audubon even seems to have on in it's logo!
You can browse the "Bird Web" on SAS site to ID lots of local birds.
https://www.seattleaudubon.org/sas/LearnAboutBirds/BirdsofWashington.aspx
Do Loons hang out in tall trees?

Also, isn't it cool that Ronald Bog park and its neighbors provide these tall trees as refuge for so many bird species?

 You can click on the photo to enlarge.

Mystery birds at Ronald Bog

It's great that Shoreline has Ronald Bog as such a great bird watching location.

Thanks Bird Watchers!